Device for burr removal from butt-welded chain links



United States Patent Inventor Adolf Englisch Colgne-Raderthal, Germany Appl. No. 756,223

Filed Aug. 29, 1968 Patented Dec. 1, 1970 Assignee Meyer, Roth & Pastor Colgne-Raderberg, Germany a firm of Germany Priority Sept. 9, 1967 Germany No. 1,627,711

DEVICE FOR BURR REMOVAL FROM BUTT- WELDED CHAIN LINKS 5 Claims, 7 Drawing Figs.

U.S. Cl. 90/24, 90/31 823d 5/02 90/2401 [5 6] References Cited UNITED STATES PATENTS 2,737,013 3/1956 Gora 90/24X 2,824,420 2/1958 Esser et al 90/24-05-X FOREIGN PATENTS 992,786 5/1965 Great Britain 90/24-01 993,206 5/1965 Great Britain 90/24-01 Primary Examiner-Gil Weidenfeld Attorney-Richards & Geier I mum" DEVICE FOR BURR REMOVAL FROM BUTT-WELDED BRAIN LINKS This invention relates to a device for the complete burr removal from butt-welded chain links.

Chain links may be preliminarily bent to a C-shape and then their ends are butt-welded by electrical resistance or blazing processes. In prior art burr was removed from such chain links by a device having two cutters which are applied tangentially to the circumference of the chain within the range of the burr and in this position are swingable to the extent of about onehalf of the circumference of the chain. In this known construction the chain link is held firmly and a swingable support is provided which has a recess shaped as a circular segment and provided with guides. The support can be swung over the fixed link in such a manner' that the chain axis is located in the center of the support opening. A disc-shaped ring is mounted in this support opening and is also provided with an opening so that it can be swung over the chain link uniformly along with the support. A double knife is fixed to this open disc-shaped ring. The double knife is U-shaped and extends inwardly; in the operative position'its sides extend to the link within the range of the burr and the ends of these sides are provided with cutters which in a tangential point of contact extend opposite each other along circumferential lines and engage the burr in opposite directions. By swinging the disc-shaped ring to about 180, each knife takes over one-half of the circumference that burr is removed from the entire circumference. At the end of the swinging disc-shaped ring is turned back to its initial position and the support is swung outwardly.

A device of this type cannot be provided in chain-welding machines for the removal of warm burr for practical reasons, namely, since there is no room in such machines to accommodate the numerous and large parts of this device. For this reason the device has not been adapted in practice.

An object of the present invention is to provide a device which also operates with two cutters and removes burr by scaling upon the entire circumference of the welded portion, whereby just as in the prior art device, the two cutters can be applied tangentially to the burr section and in this position are swingable to about one-half of the chain circumference, the device being so constructed, however, that it can be directly attached to chain-welding machines for burr removal in cold but particularly in warm state, without limiting the space for the other parts of the machine, particularly the saddle with the link, the upsetting steels and the electrodes, as well as the various members which support and move them.

Other objects of the present invention will become apparent in the course of the following specification.

During the accomplishment of the objectives of the present invention it was discovered that it is much better not to guide a single device having two knives transversely to the chain axis to the burr, as was done in prior art, but to guide the knives from the side to the burr. A further basic discovery which supplied the solution provided by the present invention is that for the same reasons it is better not to cause the knives to engage from the same side, but to bring them into position one after the other even though this procedure requires somewhat more time. Since durational requirements are not very high for the usual high cutting speeds, the use of two consecutive steps for burr removal does not present any insurmountable obstacles, particularly since this was found to be so in a different connection. Thus as far as the process is concerned, the operation of the present invention differs from prior art in that the burr removal takes place in two consecutive steps, with about onehalf of the burr circumference being removed in the course of each step.

When taking into consideration the above basic factors, the present invention is concerned with a device for burr removal from chain links which comprises two knife holders movable longitudinally and rotatable in fixed supports, the axes of which extend in the axis of rotation of the link within the range of the weld butt and which have bent ends directed to the link, as well as peeling knives which are adjustable in the bent ends of the knife holders tangentially to the circumference of the chain. It is also advisable to provide a tangentially extending additionalcutter at least upon the knife which cuts first, or upon both knives. whereby this cutter initially cuts into the burr without removing it when the knife is shifted over from the side and before the burr is scaled off upon the half of the circumference.

It is apparent that in the simplest and thus most advantageous knife holder construction the cutter is guided to the outer circumferential line of the chain to make the knife construction as simple as possible, while at the same time it is also possible to advance the cutter up to the inner circumferential line.

The present invention is applicable to a variety of forms, for example, it is also applicable to straight butt-joined welded steel lengths, whereby the advantage of the process of the present invention consists in that it can be used directly after the butt joint welding, but obviously can be also used independently thereof, irrespective as to whether the welding took place as a fire welding, autogenous welding, electrical welding, resistance welding or blaze-off welding. When open steel lengths are used the use of a single knife is required. However, the use of two knives is necessary in the case of closed parts, such as circular or oval rings, buckles, and particularly C- shaped prebent links of theselected embodiment, when a complete burr removal is desired. If only a partial burr removal is required, the use of a single knife will be sufficient.

The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawings, showing by way of example, preferred embodiments of the inventive idea.

In the drawings:

FIG. 1 is a perspective view of a link-welding machine pro vided with a burr-removing device of the present invention.

FIG. 2 is a front view of a portion of the link-welding machine of FIG. 1.

FIG. 3 shows diagrammatically a burr-removing device illustrated in FIG. 2 on an enlarged scale.

FIG. 4 is a section along the line IV-IV of FIG. 3.

FIG. 5 is a section along the line V-V of FIG. 3.

FIG. 6 is a diagrammatic side view, partly in section, illustrating a different construction of a burr-removing device.

FIG. 7 shows diagrammatically the device actuating the knife holders.

The link-welding machine shown in FIGS. 1 and 2 includes a machine frame 10, a post 11 and a casing 12 with the usual parts of the machine, particularly the electrodes 13 and the upsetting steels 14 (FIG. 2). The chain 15 which is to be treated is guided by a supplying ledge 16 to a saddle 17 in such manner that each second chain link 18 stands upon the saddle, on which it is held by the upsetting steels and is welded by the electrodes.

Directly after the placing of the link, the burr removal takes place by the device shown in FIGS. 3 to 5. As shown in FIG. 2 supports 19 are located above the steels I4 and carry knife holders 20 having the shape of connecting rods and movable longitudinally in the directions of the arrows 21 (FIG. 3) and also rotatable in both directions of the arrows 22 and 23 shown in FIGS. 4 and 5 The longitudinal movements can be carried out by means of a cylinder 40 and piston 41 (FIG. 7), while the rotational movements take place by a rack 24 and pinion 25 (FIG. 2).

As shown in FIG. 3 the ends 26 of the knife holders 20 are bent sidewise and are provided at their free ends 27 with chisellike knives 28 which are held therein adjustably and replaceably. The setting takes place in that the cutting edges of the knives 28, which are shown as being straight in the illus trated embodiment, lie against the upper circumferential line of the link circumference, which extends upon the meridian plane. In their initial positionsthe knife holders are so located that the knives are outside the range of the link.

During the burr removal, initially the right-hand knife holder 20 is shifted against the link in the direction of the arrow 21 and cuts into the burr of the link with the auxiliary cutter 31 to such an extent that the actual peeling cutter 29 reaches the desired position. The consumption of energy in the longitudinal direction of the chain link is quite small since the burr is not yet removed but is only cut into. Thereupon the knife holder 20 is rotated clockwise in the direction of the arrow 22 (FIG. 4) to the extent of somewhat more than 180 and thereby peels off one-half of the burr, which remains hanging, however, upon the other half. Directly thereafter the knife holder is moved back to its initial position. At the same time the other knife holder 20 which is constructed and arranged syrnmetrically to the first knife holder as far as the meridional plane as well as the burr surface are concerned, is moved to the corresponding position; during its longitudinal movement it cuts off the first burr half which then falls off. Directly thereafter it peels off the other burr half which also is dropped off freely, and then it returns into its initial position.

The embodiment illustrated in FIG. it differs from the described one in that the two knife holders are not located in mirrorlike symmetry but are mounted telescopically upon one side of the burr plane. Thus the knife holder 32 consists of a basic tubular body while the other knife holder 33 consists of a rod slidably mounted and guided therein and provided with a bent end 34 carrying a knife 35. The bent portion 36 of the tubular knife holder 32 is somewhat larger so as to provide free movement for the knife holder 33 with its bent portion 334. in order to provide the knife 37 of the knife holder 32 with the same stability and rigidity, its shank 38 is made wider than the cutting edge 29. This device has thus constructional drawbacks as far as different shapes of the bent portions are concerned, but it does have the constructional advantage that both sides are located upon a single side of the burr and that the other side is free.

It is apparent that the above examples have been given solely by way of illustration and not by way of limitation and that they are capable of many variations and modifications within the scope of the present invention. In all cases, but particularly when the chain axes are curved in the range of the burr weld, for example, in the case of round rings, oval rings, etc., the cutter of the knives should be made as short as possible and not longer than the corresponding width of the burr. All such and other variations and modifications are to be included within the scope of the present invention.

1 claim:

1. A device for the removal of burrs from a welded chain link, said device comprising two knife holders, supports carrying said knife holders, means moving said knife holders back and forth in the direction of the longitudinal axis of the link being treated, means rotating said knife holders about said axis, said knife holders having offset ends extending toward said link, and peeling knives carried by said offset ends perpendicularly to said axis and tangentially to the circumference of said link and having cutting edges extending parallel to the circumferential lines of said link, at least one of said knives having an auxiliary cutter extending perpendicularly to said circumferential lines.

2. A device in accordance with claim 1, wherein said knife holders and knives are located symmetrically to a central plane extending through the link.

3. A device in accordance with claim 1, wherein said knife holders fit into each other telescopically and are located upon one side of the link burr, one of said knife holders having a larger and differently shaped offset end than the other knife holder.

4. A device in accordance with claim 3, wherein the peeling knife carried by said one knife holder has a narrow cutting edge and a wider blade integral with said cutting edge.

:5. A device in accordance with claim 1, having means operating one of said knives ahead of the other knife. 

